Transducer



June 1, 1965 e. D. SEARS ETAL 3,137,116

- TRANSDUCER Filed Sept. 20, 1961 Gare/0* .0. Jean:

Pa fr/ck M Ju/// Var;

INVENTORJ United States Patent 3,137,116 TRANSDUCER Garold D. Sears and Patrick M. Suliivan, Houston, Tex., assignors of one-third to E. J. Masher and one-third to Harry J. Mosser, both of Houston, Tex.

Filed Sept. 20, 1961, Ser. No. 139,491 3 Claims. (Cl. 179-4115) This invention pertains generally to transducers and particularly to sound reproducers.

Great emphasis has been placed recently uponirnproving the engineering design of loudspeakers to thereby reproduce high fidelity sound having dynamic ranges of high quality definition of frequency response throughout the entire maze of audible sound. Design concepts of such high fidelity loudspeakers have generally followed the principle of creating sound waves by the movements of a flexible and light weight loudspeaker cone. Usually the cone is constructed of paper or other flexible and light weight material. in the air thereby causing sound waves to be developed. Although loudspeakers utilizing a cone to impart sound waves upon the air have been developed to a high degree, the efiiciency in acoustic output, fidelity and definition of frequency response, and dynamic range capabilities with respect to complex sound of such loudspeakers has not been completely satisfactory. Further, known loudspeakers have not provided satisfactory service under adverse ambient conditions such as inclement weather. known loudspeakers are used out of-doors, the loudspeaker cones and other parts have required frequent, costly repair and replacement.

Thus, it is an object of the present invention to provide an improved transducer of the sound reproducing type.

Another object of the present invention is to provide a sound reproducer wherein sound vibrations are imparted to the molecular structure of air in response to vibrations in the molecular structure of substantially rigid material having slight flexibility.

A further object of the present invention is to provide a sound reproducer having a plurality of panels of varied shape and size, and made of solid and highly flexible materials such as w-ood, plastics or metals, such panels being rigidly mounted to each other to provide novel resonating cavities.

Yet a further object of the present invention is the utilization of a plurality of panels of solid material fastened to each other by bridging posts and sounding posts thereby providing resonating cavities wherein electrical driving means is mounted to impart sound vibrations to the molecular structure of such panels by direct action as well as conduction through the bridging posts and sounding posts.

A still further object of the present invention is to provide a sound reproducer wherein molecular vibrations of air surrounding the plurality of surfaces of the sound reproducer panels resonate within cavities of the sound reproducer to efiect an acoustic output of high fidelity in frequency response and quality of definition and dynamic range.

Also an object of the present invention is to provide an inexpensive sound reproducer which is particularly adaptable for use outdoors and in high humidity, corrosive atmospheres.

In the drawings, FIGURE 1 is a perspective view of a transducer which incorporates the present invention;

FIGURE 2 is a cross-sectional plan view of the trans ducer shown in FIGURE 1, taken along lines 22 there of; and

FIGURE 3 is a sectional elevational view taken along line 3-5 of FIGURE 2.

Briefly stated, the invention is in a transducer which is Movement of the cone creates motion When dhldld particularly adaptable for use as a sound reproducer. The transducer includes a plurality of panels which may be disposed in a plurality of parallel planes with sounding posts and bridging posts being used to space the panels away from each other and to conduct sound waves to the surfaces of the panels. The panels may be of varied configuration so long as a spaced relationship exists. Disposed in one of the panels is a driving means which may be energized electrically. Disposed on the driving means and coupled to an outer panel is a tubular member which is aligned with the driving means by suitable fastening means such as known spider construction. The tubular member has movement imparted to it, as for example, through energization of the driving means. Such movement of the tubular member initiates wave vibrations in the outer panel and the combination of bridging posts, sounding posts, and cavities formed between the panels provides improved, high fidelity sound reproduction.

Referring now to the drawings in detail, FIGURE 1 shows a rear resonating panel 19 coupled to a center resonatingpanel .12 by a plurality of rear bridging posts of which posts 16, 17, and 18 are visible in FIGURE 1. Slot 42, to be explained in more detailsubsequently, is partially visible in FIGURE 1.

A front resonating panel-14 is disposed from center panel 1-2 by a plurality of trout bridging posts such as posts 36, 3-2, 34, 36, 38, and 4% the endsof which are visible in FIGURE 1. Seal 22 and sounding post 20 are also visible in FIGURE 1.

FIGURE 2 is a plan view showing the internal construction of the transducer. The resonating panels 10, 12,

and 14 may be constructed of any solid material such as wood or plastic;

Sounding post 20 and the bridging posts may be fastenedto the panels with screws, glue, or other suitable fastening means. The bridging posts and sounding post impart motion to the panels which are also acted upon by air molecules on the surface of each panel.

A driving means is positioned on and coupled to the center panel 12. Such driving means, in the embodiment of the invention shown, includes a magnet structure 5%, driving tube 52, spider 54, and coil 56. The magnet structure 50 includes a center pole piece 69 and poles s2 and 64. Tube 52 passes through an aperture as in the center panel 12 for positioning over center pole piece at}. Tube 52 has a recessed portion 68 whereon coil 56 is wound so as to be disposed over pole piece 60 and between poles 62 and 64 for movement in response to electrical impulses I in a known manner.

-In order to insure friction-free movement of tube 52 over pole piece .60, spider 54 is fastened by suitable means 7% such as glue to tube 52. Spider mount '72 is coupled to the center panel 12 and to spider 54. A seal 22 is positioned in panel 14 over the end of tube 52 to insure proper protection to the inside of tube 52 and proper bonding of tube 52 to panel 14.

Thus, movement imparted to tube 52 by the coil and magnet assembly is conducted to panel 14. The bridging posts, sounding post, panels, slots, and resonating chambers between the panels provide improved, high fidelity sound through combined molecular action or" the air and solid materials.

FIGURE 3 is an elevational view taken along lines 3-3 of FIGURE 2 thereby showing the spider 54 and driving tube 52 in more detail. Spider 54 has cars 83, 82, 84, and 86 which may have apertures therein.

Each car on the spider may have a protrustion similar to protrusion 88 on ear 82. Fasteners such as screw or mount 72 are used for coupling the spider to the center panel 12. Any spider which fixedly supports the driving tube is satisfactory.

Thus, the invention provides an improved transducer said driving means.

for changing electrical signal energy into acoustical energy.

Such transducer combines mutual radiation impedance of the surfaces of a plurality of panels with the resonating chambers formedby such panels to thereby provide an While known sound reproducers usually require cone replacement and cone centering, the transducer incorporating the pre-sent invention alleviates the necessity of cone repairs or other repairs.

, Although a preferred embodiment of the invention has been shown and described, the invention is defined by the following claims.

Wecl-airn: 1 1

1. A sound reproducer including a central panel mern her having .aplurality of surfaces and a plurality of apert-ures, iarrear panel member in spaced relation to said central panel member, first tfiastening rneans coupled between one surface ocE said central panel member and said rear panel member, a ttrontpanel member in spaced relation to said central panel member, said frontlandsaid rear panel members being on :oppositesides of said central panel member, second fastening means coupled bet-Ween a surface of said central panel member and said tfront panel member, sounding post 'mea'ns coupledbet ween said ,front panelrnembernand said rear panel member through one of said apertures in said central panel member, .and

driving means coupled to said central panel member and "to saidtiron-t panel member forimpa-rting acoustic-a1 output theret-oin response to electrical energy supplied to a 2. A transducer adapted forreproducing sound in relsponse' to electrical signal impulses applied to driving, ineans pos-itioned on said transducer including inyeombination, H I

a rear panel of substantially rectangular configuration, a center panel of substantially reetangular'oonfignra- I tion disposed in spaced, parallel relationship tosaid rear panel, said center panel having a substantially circular-aperture in the central portion thereof and.

adapted to receive driving means, said center panel further including a first elongated opening :on one side of said circular aperture and a second elongated 'opening on the other side of said circular aperture,

a front panel of substantially rectangular configuration disposed in spaced, parallel relationship to said center panel and ion the opposite side of said center panel from said rear panel, said front panel having a plurality of .apertureswith at least one of said apertures adapted to receive "driving means,

a sounding post coupled between said none and rear panels and disposed in one of said first and second elongatedopenings in said center panel, said sounding post being positioned in one of said apertures of said from panel, I i g V a plurality of front bridging posts dis-posed in :all but 'two of saidapertures in said front panel and coupled to said center panel so that said frontipanel initiates acoustic outputin response to electrical signals provided to driving'me'ans, andp "a pl-urality of rear bridgingposts coupled between said center panel and said rear panel whereby said soundi-ng post imparts sound vibr-ations "to said frear panel in response to vibrations-of said front panel.

' 3. A transducer defined lay claim :2 wherein said front panel, said center panel, and said rear panel are construeted of non-corrosive material.

I References Cited by the Examiner UNITED STATES PATENTS 1,710,463 4/29; Wilhelm et a1. {17 9415 1,726,533 9/29 Baldwin ;179 11s' 1,764,015 .6/ Goodyear 179 4.16 1,819,499 8/31 Conrad 181+3,1 1,882,401: 10/32 Pierce 179 11s,

I FOREIGN PATENTS I Y N 920 ,7 7/49 Germany. I

328,840 5/30 Great Britain.

ROBERT osie, Primary Exdhiirier. 

1. A SOUND REPRODUCER INCLUDING A CENTRAL PANEL MEMBER HAVING A PLURALITY OF SURFACES AND A PLURALITY OF APERTURES, A REAR PANEL MEMBER IN SPACED RELATION TO SAID CENTRAL PANEL MEMBER, FIRST FASTENING MEANS COUPLED BETWEEN ONE SURFACE OF SAID CENTRAL PANEL MEMBER AND SAID REAR PANEL MEMBER, A FRONT PANEL MEMBER IN SPACED RELATION TO SAID CENTRAL PANEL MEMBER, SAID FRONT AND SAID REAR PANEL MEMBERS BEING ON OPPOSITE SIDES OF SAID CENTRAL PANEL MEMBER, SECOND FASTENING MEANS COUPLED BETWEEN A SURFACE OF SAID CENTRAL PANEL MEMBER AND SAID FRONT PANEL MEMBER, SOUNDING POST MEANS COUPLED BETWEEN SAID FRONT PANEL MEMBER AND SAID REAR PANEL MEMBER THROUGH ONE OF SAID APERTURES IN SAID CENTRAL PANEL MEMBER, AND DRIVING MEANS COUPLED TO SAID CENTRAL PANEL MEMBER AND TO SAID FRONT PANEL MEMBER FOR IMPARTING ACOUSTICAL OUTPUT THERETO IN RESPONSE TO ELECTRICAL ENERGY SUPPLIED TO SAID DRIVING MEANS. 